1. Field of the Invention
The present invention relates generally to a heat dissipation module comprising fins, and in particular to a finned heat dissipation module having guides for switching airflow between different air passages to enhance efficiency of heat dissipation.
2. Description of the Prior Art
The development of computer technology makes the power consumption of a computer device dramatically increased. Thus, a heat dissipation module is commonly employed in the recent computer devices or other electronic devices to remove heat from the computer or electronic components that generate heat in order to maintain proper operation temperature of the computer or electronic devices. Some heat dissipation devices incorporate a fan that induces air streams flowing through the heat dissipation device to facilitate heat removal by forced heat convection.
Some conventional heat dissipation devices are comprised of fins arranged in rows with air passages formed therebetween. The air passages are often linear or straight to allow for easy flow of air therethrough. However, such a linear configuration limits heat exchange between the airflow and the fins for air flows through the fins quickly. As a consequence, the efficiency of heat removal is not optimal and the life span of the computer or electronic components is often reduced.
Factors that are often taken into consideration for overcoming heat removal problem include performance of the computer components, which leads to reduced energy consumption and generates less heat during the operation thereof, and geometric configuration, which enhances heat exchange rate between the heat generation component and a heat dissipation device for more efficient removal of heat.
A state-of-art heat dissipation module, generally employed in a notebook computer that requires more severe heat management than regular desktop computers, comprises a thermally conductive casing in physical contact with a surface of a heat source, such as a central processing unit of a notebook computer. The casing forms a fan chamber in which a fan is received and fixed and an air channel in which a plurality of fins is arranged to define a plurality of air passages through which airflow from the fan may pass to initiate heat exchange with the fins and thus removing heat from the fins, as well as the casing.
FIG. 1 of the attached drawings show an example of the conventional heat dissipation module housed in a casing. As mentioned above, the air channel of the heat dissipation module comprises a plurality of fin plates 100 parallel to each other to define a plurality of air passages 103 therebetween, each air passage extending from an inlet 101 to an outlet 102. Airflow 105 generated by a fan often moves in a direction that is not parallel to the passages 103. Thus, when the airflow enters the inlet 101, the air goes in an oblique direction and impacts the surface of the fin plate 100, which imparts a resistance to the airflow, causing a turbulence 105a. Also, a secondary turbulence 105b is formed by the airflow “reflected” by the fin plate to hit an adjacent fin plate. The turbulences 105a, 105b are then combined in a downstream location, forming a substantially unified air stream 105 that passes through the air passage 103.
Although heat can be effectively carried out by the heat dissipation module described above, the heat dissipation module cannot offer the optimum efficiency in removing heat and usually makes great noises.
Thus, the present invention is aimed to provide a heat dissipation module that overcomes at least some of the drawbacks of the conventional devices.